Mr Robertson, who has overseen the group’s international expansion, will stay at the company in a non-executive role.

The chief executive job will be handed to Nick Beighton, who was promoted to chief operating officer last October. The changes will take effect immediately.

Nick Robertson started Asos 15 years ago

Asos has recently added Helen Ashton, former chief executive of debt management group Capquest, to its board as chief financial officer.

Ms Ashton, who only started at the retailer this week, will take on responsibilities that will free up Mr Beighton to handle the chief executive role.

Mr Robertson continues to own a 8.4pc stake in Asos, worth around £180m. In January he sold nearly 750,000 shares, worth £20.2m, after a large tax bill.

Brian McBride, chairman of Asos, said: "On behalf of everyone who works at Asos, I'd like to acknowledge Nick Robertson's extraordinary achievement. His passion and vision have built a start-up into a world class company. We are all delighted that Nick will continue to contribute to the company that he started.

"We are fortunate to have such an able successor for the CEO role in Nick Beighton. Nick has unique experience of the company built over six years, equipping him to drive Asos along its growth trajectory to become the world's leading online fashion retailer for 20 - somethings".

Asos has become an online success story Photo: PA

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